TY - JOUR A1 - Oertel, Mario A1 - Bung, Daniel B. T1 - Stability and scour development of bed material on crossbar block ramps T2 - International journal of sediment research N2 - Block ramps are ecologically oriented drop structures with adequate energy dissipation and partially moderate flow velocities. A special case is given with crossbar block ramps, where the upstream and downstream level difference is reduced by a series of basins. To prevent the total structure from failing, the stability of single boulders within the crossbars and the bed material in between must be guaranteed. The present paper addresses the stability of bed material and scour development for various flow regimes. Any bed material erosion may affect the stability of the crossbar boulders, which in turn can result in major damages of the ramp. Therefore new design approaches are developed to choose an appropriate bed material size and to avoid failures of crossbar block ramp structures. Y1 - 2015 UR - https://opus.bibliothek.fh-aachen.de/opus4/frontdoor/index/index/docId/7451 SN - 1001-6279 VL - 30 IS - 4 SP - 344 EP - 350 PB - Elsevier CY - Amsterdam ER -